Make Compost from Kitchen and Garden Waste

I feel like I’m on a bit of a gardening theme at the moment but we are really trying to grow our own veggies, the pandemic has taught me that it’s good to be a little self sufficient! One of the things that we use a lot but which can be expensive is compost, but you can make it more cheaply than you realise using your kitchen and garden waste. Composting is an efficient, cost-effective method to dispose of organic waste from the garden and kitchen and to reuse in planting as a soil amendment.

Grow, eat, trim, mow, don’t throw! Naturally occurring microbes in organic material break down and convert garden and kitchen wastes into one of nature’s best mulches and soil amendments. Compost uses the natural processes of decomposition to return organic materials to the soil, allowing these materials to be used again in a classic example of the ‘reuse’ concept. Compost takes garden waste and plant-based kitchen scraps and natural decomposition processes to make a mixture used to improve the soil and reduce commercial fertiliser use.

Kitchen and Garden Compost Materials

Good compost is made from soft plant materials such as leaves, grass clippings, weeds, faded flowers, vegetable peelings, straw, shredded newspapers (not shiny or coloured pieces, though). A good option for grass clippings is to leave the collector bag off, and let the clippings decompose right back into the lawn. (Although this can get messy with two kids and a dog running around, it may also turn them green!) If putting grass clippings in the compost, be sure to mix the pile well. Grass clippings pack down into a tight pile that can be difficult to decompose.

Sawdust and wood chips can be composted, but require adequate nitrogen and take more time. Add grass clippings or a fertiliser high in nitrogen to help these materials decompose.

Do not attempt to compost branches, the Christmas Tree, or other woody materials. They allow too much air space in a pile, which keeps it too cool and take a very long time to decompose. Take these materials to a community garden waste collection centre or use your Garden Waste Council bin. Do not add pet waste. (Yuk!) Do not add the ash from charcoal or wood burners.

Avoid putting diseased or insect-infested plant materials in the compost pile; it does not get hot enough to kill any pathogens. Weeds are fine, but keep seed heads out to avoid re-introducing the weeds when the compost is used. These materials should be put in the bin to be removed to avoid re-contamination.

Kitchen Scraps for Compost

Plant-based products such as fruit and vegetable peels and trimmings are excellent additions. Do not add kitchen waste that is protein-based, such as eggshells, meat, bones, drippings, and grease or dairy products. These materials slow the decomposition and may attract rodents and other pests.

How Do These Materials Turn into Compost?

Four things are needed to make compost: green materials for nitrogen, brown materials for carbon, water, and air.

 Green materials such as vegetable peelings and grass clippings add nitrogen, which provides food for the microbes. In the completed compost, nitrogen adds an essential nutrient back into the soil.
 Carbon from the brown sources such as dried grasses and weeds provides energy for the microbes as they work on breaking down the materials.
 Like all natural processes, air (oxygen) and water are needed to complete the process. Water helps move the microbes around the pile.

These ingredients create heat as they work together, providing the correct environment for the microbes that do the work.

Build or Buy a Compost Bin or Container

There are many simple plans for building a compost bin that can be found on the internet with a quick search. Many garden centres and DIY stores sell compost bins that are attractive and take little space. The one below has excellent reviews and is on special offer at the moment.*

Making Compost

Position the container or bin at least 2 feet from the house, with easy access to water. Make it easy to move garden waste to the site, and not far from the kitchen.

Mix organic materials as they are added. Spray with a little water to speed decomposition. Keep it moist, but not soaked. Turn the pile weekly with a spade or fork to introduce air regularly and aid in the decomposition and control odors. Active compost will heat to 120 to 160 degrees in the center of the pile. Heat is needed to encourage the bacterial process and help sanitise the interior of the pile.

In cold climates, stop turning the pile in the Autumn to allow the heat to be retained. Start turning in the Spring to start the process again.

Compost is ready to use when the pile is one-half of the original size, no longer resembles leaves and potato peelings, and has a pleasant earthy smell.

Using Compost from Kitchen and Garden Waste

 Add compost to sandy soils to improve water retention and to clay soils to improve drainage. While compost is not a fertiliser, it does add nutrients to soil.
 Use compost to improve soil structure, mulch plants, or as potting soil for house plants.
 Turn potato peelings and grass clippings into an asset for your garden.

There is a great tip sheet for ways to use your compost here.

If you’re interested in getting a garden going, you will also like Starting a New Garden Plot at Home and How to Make Raised Beds for Veggies.

*Affiliate link which means I get a tiny percentage of the sale if you buy but costs you nothing extra. Special offer correct at time of posting.